Atomic Layer Deposition (ALD) is a burgeoning technology that has enabled the precision ‘one-atomic-layer by one-atomic-layer’ fabrication of thin films and free-standing materials. To date, a wide range of materials have been prepared by ALD including oxides, nitrides, sulfides and pure noble metals. In addition to inorganic materials, ALD of organic, polymeric materials has been reported recently.
In previous work, co-inventors of the present disclosure described ALD of hybrid organic-inorganic polysilsesquioxane thin films, and their conversion to high flux, high selectivity microporous membranes by subsequent removal of bridging organic groups from the organosilicate framework. Jiang, Y. B. et al., J. AM. CHEM. SOC. 2007, 129, 15446-15447. Overall there is a continuing need to extend ALD to new materials classes and structures with precisely designed, optimized properties.
The fabrication of biologically-inspired or biomimetic materials has gained increasing attention for applications in areas such as medicine, environmental monitoring and remediation, energy conversion, and bioengineering. Various polypeptides, which are polymers composed of amino acid subunits, have been synthesized by conventional liquid-phase or solid-phase processes, such as are disclosed by Han, S. Y. et al., Tetrahedron 2004, 60, 2447-2467; and Venkatesan, N. et al., Chem. Rev. 2006, 106, 3712-3761. However, these processes are time and labor-intensive and are not suitable for depositing thin films.
Demonstrating the feasibility of using a novel ALD process to precisely construct biomimetic materials would be a step forward in the art.